LVM 扩容根分区

硬盘太小，不够用，LVM扩容根分区

 

增加一块硬盘，如下图所示:

 

二、

[root@tmp ~]# mount       #通过mount命令让我们知道/dev/mapper/vg_tmp-lv_root  文件系统为ext4

/dev/mapper/vg_tmp-lv_root on / type ext4 (rw)

proc on /proc type proc (rw)

sysfs on /sys type sysfs (rw)

devpts on /dev/pts type devpts (rw,gid=5,mode=620)

tmpfs on /dev/shm type tmpfs (rw)

/dev/sda1 on /boot type ext4 (rw)

none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)

[root@tmp ~]# lsblk             #通过lsblk 可看出vg_tmp-lv_root 就是挂载到 / sdb这块硬盘100G未使用

NAME                      MAJ:MIN RM  SIZE RO TYPE MOUNTPOINT

sda                         8:0    0   20G  0 disk

├─sda1                      8:1    0  500M  0 part /boot

└─sda2                      8:2    0 19.5G  0 part

  ├─vg_tmp-lv_root (dm-0) 253:0    0 17.6G  0 lvm  /

  └─vg_tmp-lv_swap (dm-1) 253:1    0    2G  0 lvm  [SWAP]

sdb                         8:16   0  100G  0 disk 

sr0                        11:0    1  395M  0 rom  

 

[root@tmp ~]# mkfs.ext4 /dev/sdb #格式化/dev/sdb 为ext4

 

[root@tmp ~]# pvcreate /dev/sdb    #把/dev/sdb 创建成一个pv

  Physical volume "/dev/sdb" successfully created

[root@tmp ~]# vgs     # vgs 命令可以查看卷组，一个一卷组vg_tmp

  VG     #PV #LV #SN Attr   VSize  VFree

  vg_tmp   1   2   0 wz--n- 19.51g    0

 

[root@tmp ~]# vgextend vg_tmp /dev/sdb       #把/dev/sdb 加到vg_tmp 这个卷组上

  Volume group "vg_tmp" successfully extended

[root@tmp ~]# vgdisplay    #vgdisplay 命令可以看出free  pe 有100G

  --- Volume group ---

  VG Name               vg_tmp

  System ID             

  Format                lvm2

  Metadata Areas        2

  Metadata Sequence No  4

  VG Access             read/write

  VG Status             resizable

  MAX LV                0

  Cur LV                2

  Open LV               2

  Max PV                0

  Cur PV                2

  Act PV                2

  VG Size               119.50 GiB

  PE Size               4.00 MiB

  Total PE              30593

  Alloc PE / Size       4994 / 19.51 GiB

  Free  PE / Size       25599 / 100.00 GiB

  VG UUID               yxzyS0-iYIh-BuLX-n3hc-M5Bh-U8IL-BdBjwC

[root@tmp ~]# lvextend -L +99.95G /dev/mapper/vg_tmp-lv_root   #99.95G 挂载到/dev/mapper/vg_tmp-lv_root，如果写100G可能会不成功，块大小等！

  Rounding size to boundary between physical extents: 99.95 GiB

  Size of logical volume vg_tmp/lv_root changed from 17.57 GiB (4498 extents) to 117.52 GiB (30086 extents).

  Logical volume lv_root successfully resized [root@tmp ~]# resize2fs /dev/mapper/vg_tmp-lv_root

[root@tmp ~]# resize2fs /dev/mapper/vg_tmp-lv_root            #更新/dev/mapper/vg_tmp-lv_root  分区大小

resize2fs 1.41.12 (17-May-2010)

Filesystem at /dev/mapper/vg_tmp-lv_root is mounted on /; on-line resizing required

old desc_blocks = 2, new_desc_blocks = 8

Performing an on-line resize of /dev/mapper/vg_tmp-lv_root to 30689280 (4k) blocks.

The filesystem on /dev/mapper/vg_tmp-lv_root is now 30689280 blocks long.

 

[root@tmp ~]# df –h   #查看根分区是否扩容

Filesystem            Size  Used Avail Use% Mounted on

/dev/mapper/vg_tmp-lv_root

                      116G  795M  109G   1% /

tmpfs                 491M     0  491M   0% /dev/shm

/dev/sda1             477M   30M  422M   7% /boot